Wireless communication systems are widely used to provide voice and data services for multiple users using a variety of access terminals such as cellular telephones, laptop computers and various multimedia devices. Such communications systems can encompass local area networks, such as IEEE 801.11 networks, cellular telephone and/or mobile broadband networks. The communication system can use a one or more multiple access techniques, such as Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Code Division Multiple Access (CDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA) and others. Mobile broadband networks can conform to a number of system types or partnerships such as, General Packet Radio Service (GPRS), 3rd-Generation standards (3G), Worldwide Interoperability for Microwave Access (WiMAX), Universal Mobile Telecommunications System (UMTS), the 3rd Generation Partnership Project (3GPP), Evolution-Data Optimized EV-DO, or Long Term Evolution (LTE).
Some systems, such as LTE, strive to serve densely populated areas with very high data rates. One way in which an LTE network can provide dense coverage and high data capacity in a cost effective manner is to utilize Relay nodes (RNs), which function as base stations to used devices, but do not have a backhaul connections as base stations do. Instead, the RN communicates with an LTE base station (eNB) via a standard LTE radio link.
One of the functions of the eNB and RN is allocating bandwidth resources to user devices. LTE uses OFDMA for physical layer signaling in the downlink and SC-FDMA in the uplink. Bandwidth in these signaling schemes is shared among multiple users by allocating resource blocks having a portion of spectrum for a certain number of symbol periods. In LTE, the eNB allocates resource blocks to the RN, which, in turn, allocates resource blocks to user devices in communication with the RN. The eNB, however, does not have full knowledge of the status of individual user devices in communication with the RN. Rather the eNB relies on feedback from the RN in order to determine how many uplink and downlink resources to allocate to the RN.
In some relay systems, the relay communicates with a base station using flow control techniques. Such flow control techniques include, for example, signaling the base station to stop sending data whenever the relay node has too much data. Other techniques include, for example, the relay providing the base station with a per-user breakdown of data resources being used. As more information is sent back to the base station from the relay, however, system latency increases and a higher amount of bandwidth resources becomes devoted to status signaling.